A two-word email sent on the eve of the Oct. 10 Million Man March prompted Capitol Police to confiscate the gun and badge of a newly promoted captain, only to return both items on Oct. 13.

The incident is still under investigation, according to outgoing Chief Kim C. Dine, who credits the department with taking “swift and appropriate action” when employees misbehave. But a congressional aide familiar with the captain’s case said the agency's “old boys' network is attempting to make an example of a woman who has a reputation for calling out improper behavior.” The original message, sent at 8:41 a.m. by an administrative officer in the department’s Protective Services Bureau, notified a few dozen employees that the security pin color for the week ahead would be, “BLACK.”

McBride sent a second response, two minutes after the first, directly to the sender.

"Of course you can feel free to take me off this notification any time you'd like. I don't think I will be on [dignitary protection] anytime soon :)"

But the 8:47 a.m. email ignited a firestorm.

Many of the email's recipients were black.

Tensions were running high ahead of the all-hands-on-deck event, which required some officers to log 20-hour shifts.

A day earlier, Dine sat down with Nation of Islam leaders to apologize and distance himself from an inflammatory internal newsletter — also released by the Protective Services Bureau — that warned of potential “fireworks” during Nation of Islam leader Louis Farrakhan’s visit to the Hill.

So after McBride's email chain surfaced, the chief immediately referred the matter to the Office of Professional Responsibility for investigation.

It didn't take long for the two-message chain to make its way onto the radar of the Capitol Police union.

Jim Konczos, chairman of the Capitol Police Labor Committee's executive board, fired off an email to the Capitol Police Board, asking, "at what point do you hold individuals in management to task and ask where their termination recommendations are?"

Relations between the union and management have been particularly tense during Dine's tenure, but the department has been under scrutiny for the past year over disciplinary practices in the wake of officers leaving guns in public places, including bathrooms in the Capitol .

But sources outside the department are concerned Capitol Police acted too swiftly in launching their probe of McBride, without all the facts.

"In an attempt at intimidation, they sent a USCP officer to her home to take her badge and gun, only to have both restored the next business day," the congressional source told CQ Roll Call, under the condition of anonymity to discuss sensitive personnel matters. "Now they are leaking their distorted version of the story in an attempt at public humiliation. Over half of the last set of promotions went to women who are committed to protecting the Capitol — a clear threat to the old boys' network accustomed to covering up incompetence."

McBride blew the whistle on overtime padding at her last assignment. In her second response email on Oct. 9, she allegedly called out the Protective Services Bureau for not updating its secure list after the pope’s visit.

By contrast, Capitol Police did not take the gun and badge of the deputy chief responsible for the contentious Million Man March newsletter, according to congressional sources, nor the deputy chief investigated in 2014 for sleeping with his subordinate .

While under investigation for leaving their guns unattended in the bathroom this spring, dignitary protection details for top Republican leaders maintained possession of their badges and weapons. Though not all those cases involved male employees.

"With regard to USCP policies, the Department’s Rules of Conduct, which include prohibitions against discrimination, harassment, and retaliation, are the standards to which our employees are held," Dine said in a statement to CQ Roll Call, emphasizing that the investigation into McBride's conduct is still open and active. The department will continue to address the matter internally.

"During my tenure as Chief of Police, I have emphasized and enforced these standards to all USCP employees and have held members of the agency accountable, regardless of position. Likewise, we have continued to work with our labor unions, taking the extra step of hiring a labor specialist," he continued.

"While the majority of our employees perform professionally, ethically, and with great dedication, the Department continues to take swift and appropriate action regarding potential misconduct by employees," Dine said, explaining that those cases go to the agency's inspector general, OPR or both.

Following investigation, all cases are referred to the department's disciplinary review officer for penalty recommendations. Those range from suspensions, demotions or termination.